Hydrodynamic equations well describe averaged parameters of turbulent steady flows, at least in pipes where boundary conditions can be estimated. The equations might outline the parameters fluctuations as well, if entry conditions at current boundaries were known. This raises, in addition, the more comprehensive problem of the primary perturbation nature, noted by H.A. Lorentz, which still remains unsolved. Generally, any flow steadiness should be supported by pressure waves emitted by some external source, e.g. a piston or a receiver. The wave plane front in channels quickly takes convex configuration owing to Rayleigh's law of diffraction divergence. The Schlieren technique and pressure wave registration were employed to investigate the wave interaction with boundary layer, while reflecting from the channel wall. The reflection induces boundary-layer local separation and following pressure rapid increase within the perturbation zone. It propagates as an acoustic wave packet of spherical shape, bearing oscillations of hydrodynamic parameters. Superposition of such packets forms a spatio-temporal field of oscillations fading as 1/r. This implies a mechanism of the turbulence. Vorticity existing in the boundary layer does not penetrate in itself into potential main stream. But the wave leaving the boundary layer carries away some part of fluid along with frozen-in vorticity. The vorticity eddies form another field of oscillations fading as 1/r2. This implies a second mechanism of turbulence. Thereupon the oscillation spatio-temporal field and its randomization development are easy computed. Also, normal burning transition into detonation is explained, and the turbulence inverse problem is set and solved as applied to plasma channels created by laser Besselian beams.

Detailed report on a topic that has already attracted much popular interest.

Provides fascinating reading for physicists, biologists and general readers alike.

Non Destructive Testing and Non Destructive Evaluation using Ultrasounds covers an important field of applications and requires a wide range of fundamental theoretical, numerical and experimental investigations. In the present volume, the reader will find some relevant research results on wave propagation in complex materials and structures which are concerned with today 's problems on composites, bonding, guided waves, contact or damage, imaging and structural noise. The fifth meeting of the Anglo-French Research Group on "Wave propagation in non homogeneous media with a view to Non Destructive testing" was held in Anglet, France, June 2-6, 2008.

The 17 chapters of "How to Gain Gain" give a detailed insight into a collection of the most common gain producing and constant current generating possibilities (28) of triodes for audio pre-amplifier purposes. These chapters also offer complete sets of formulae to calculate gain, frequency and phase responses of certain building blocks built-up with this type of vacuum valve (tube). In all cases detailed derivations of the gain formulae were also presented. All what is needed are the data sheet valve characteristic figures of the triode's mutual conductance, the gain factor and the internal plate (anode) resistance. To calculate frequency and phase responses of gain stages the different data sheet based input and output capacitances have to be taken into account as well. To calculate transfer functions for any kind of triode driven gain stage, including all its bias setting, frequency and phase influencing components, example MathCad worksheets as a second part of each chapter allow easy follow-up and application of the respective formulae. In addition, to demonstrate the differences of feedback and non-feedback relationships, in the last chapter and on MathCad basis, a very extensive and complete calculation example for a three stage linear pre-amplifier as well as a three stage RIAA equalized phono amplifier plays the wind up role of the book.

The 26th International Symposium on Shock Waves in G ttingen, Germany was jointly organised by the German Aerospace Centre DLR and the French-German Research Institute of Saint Louis ISL. The year 2007 marked the 50th anniversary of the Symposium, which first took place in 1957 in Boston and has since become an internationally acclaimed series of meetings for the wider Shock Wave Community. The ISSW26 focused on the following areas: Shock Propagation and Reflection, Detonation and Combustion, Hypersonic Flow, Shock Boundary Layer Interaction, Numerical Methods, Medical, Biological and Industrial Applications, Richtmyer Meshkov Instability, Blast Waves, Chemically Reacting Flows, Diagnostics, Facilities, Flow Visualisation, Ignition, Impact and Compaction, Multiphase Flow, Nozzles Flows, Plasmas and Propulsion. The two Volumes contain the papers presented at the symposium and serve as a reference for the participants of the ISSW 26 and individuals interested in these fields.

This is the second, enhanced and updated edition of an essential text for students of mechatronics. It covers both the detailed physical modeling of mechatronic systems and their precise numerical simulation using the Finite Element (FE) method. New material includes a section discussing locking effects as occurring in the numerical computation of thin mechanical structures as well as a new chapter on computational aeroacoustics to study the complex phenomenon of flow induced noise.

Computational Mechanics of the Classical Guitar describes a new dynamic paradigm in instrument acoustics based on time-dependent transient analysis and simulation of complete musical instruments. It describes the current state of theoretical and experimental research into the guitar for engineers, instrument makers and musicians. This includes a summary of the basic equations for the mechanics of vibrating bodies and a presentation of the FDM (finite difference method) model with which the true vibrational behaviour of the instrument as an entire system can be understood for the first time. This monograph presents various new theoretical and experimental results and insights into guitar playing such as the coupling between the strings and the top plate or a description of the finger noise made when the fingers slide over the strings before plucking.

Communication Acoustics deals with the fundamentals of those areas of acoustics which are related to modern communication technologies. Due to the advent of digital signal processing and recording in acoustics, these areas have enjoyed an enormous upswing during the last 4 decades. The book chapters represent review articles covering the most relevant areas of the field. They are written with the goal of providing students with comprehensive introductions. Further they offer a supply of numerous references to the relevant literature. Besides its usefulness as a textbook, this will make the book a source of valuable information for those who want to improve or refresh their knowledge in the field of communication acoustics - and to work their way deeper into it. Due to its interdisciplinary character Communication Acoustics is bound to attract readers from many different areas, such as: acoustics, cognitive science, speech science, and communication technology.

Trees can reduce noise by sound reflection and absorption and this is the first book bringing together the widely scattered literature on noise abatement by urban trees. The book will interest those concerned with environmental management, noise control, and urban forestry. It is an invaluable source of information for environmental managers, foresters, acousticians, engineers, architects, scientists, and students.

Structure-Borne Sound" is a thorough introduction to structural vibrations with emphasis on audio frequencies and the associated radiation of sound. The book presents in-depth discussions of fundamental principles and basic problems, in order to enable the reader to understand and solve his own problems. It includes chapters dealing with measurement and generation of vibrations and sound, various types of structural wave motion, structural damping and its effects, impedances and vibration responses of the important types of structures, as well as with attenuation of vibrations, and sound radiation from structures. For the third edition, the author fundamentally revised and newly organized the contents of the work. Nevertheless, the intention has been to preserve the style of the previous editions, namely to focus on the fundamentals enabling the reader to analyse further problems.

Rapid growth of the mobile communication market has triggered extensive research on the bulk as well as surface acoustic wave devices in the last decade. Quite a few important results on the modeling and simulation of Film Bulk Acoustic Resonator (FBAR) and Layered SAW devices were reported recently. The other recent advance of acoustic waves in solids is the so-called phononic crystals or phononic band-gap materials. Analogous to the band-gap of light in photonic crystals, acoustic waves in periodic elastic structures also exhibit band-gap. Important applications of phononic band gap materials can potentially be found with creating a vibration free environment in microstructures, and design of advanced acoustic frequency filter, etc. In addition to the wave electronics and phononic crystals, to facilitate the emerging needs in the quantitative nondestructive evaluation of materials, waves in anisotropic solids and/or electro-, magneto- interaction problems also regained much attention recently. Topics treated include: Waves in piezoelectric crystals; Simulation of advanced BAW and SAW devices; Analysis of band gaps in phononic structures; Experimental investigation of phononic structures; Waves in multilayered media;Waves in anisotropic solids and/or electro-, magneto- interaction problems.

Sound waves are the only practical means of remote investigation of the sea and its bottom and transmission in seawater. Underwater acoustics has become one of the major technologies used in the exploration and exploitation of the oceans for scientific, industrial, or military/naval purposes. It is widely employed in the fields of ocean engineering, seafloor mapping, defence, oceanography, navigation, and fisheries.

Dr Xavier Lurton is a renowned specialist in underwater acoustics. He has worked in this field as a scientist, engineer, project manager and teacher since 1981 and has participated in many scientific projects, systems developments and at-sea cruises. In the second edition of his book, Dr Lurton provides an updated and extended introduction to underwater acoustics, including coverage of the physical processes and their basic modeling, different underwater acoustic systems and their practical applications and a description and assessment of the various technologies. Dr Lurton has extensive experience as a lecturer in undergraduate and postgraduate schools, including naval academies. This book is based on his direct, first-hand experience of the many aspects of underwater acoustics in seas around the world, at the forefront of current research and development efforts.

The Springer Handbook of Auditory Research presents a series of comprehensive and synthetic reviews of the fundamental topics in modern auditory research. The v- umes are aimed at all individuals with interests in hearing research including advanced graduate students, post-doctoral researchers, and clinical investigators. The volumes are intended to introduce new investigators to important aspects of hearing science and to help established investigators to better understand the fundamental theories and data in fields of hearing that they may not normally follow closely. Each volume presents a particular topic comprehensively, and each serves as a synthetic overview and guide to the literature. As such, the chapters present neither exhaustive data reviews nor original research that has not yet appeared in pe- reviewed journals. The volumes focus on topics that have developed a solid data and conceptual foundation rather than on those for which a literature is only beg- ning to develop. New research areas will be covered on a timely basis in the series as they begin to mature.

Materials that can mold the ?ow of elastic waves of certain energy in certain directions are called phononic materials. The present thesis deals essentially with such phononic systems, which are structured in the mesoscale (\1 lm), and with their individual components. Such systems show interesting phononic properties in the hypersonic region, i.e., at frequencies in the GHz range. It is shown that colloidal systems are excellent model systems for the realization of such phononic materials. Therefore, different structures and particle architectures are investigated by Brillouin light scattering, the inelastic scattering of light by phonons. Both the mechanical properties of the individual colloidal particles, which manifest in their resonance vibrations (eigenmodes), as well as the acoustic propagation in colloidal structures have been investigated. The measurement of the eigenmodes allows for new insights into physical properties at the mesoscale, e.g., con?nement effects, copolymer behavior, or the non-destructive determination of nanomechanical properties of core-shell particles, supporting the working groups aim to achieve a deeper understanding of 'soft mechanics' at small length scales. Another novel contribution assigned to this thesis is the ?rst experimental rea- zation of a phononic band gap arising from the interaction of these particle - genmodes with the effective medium band (hybridization gap). This ?nding already gave new impulses to the whole ?eld of phononics.

Nowadays, music-inspired phenomenon-mimicking harmony search algorithm is fast growing with many applications. One of key success factors of the algorithm is the employment of a novel stochastic derivative which can be used even for discrete variables. Instead of traditional calculus-based gradient, the algorithm utilizes musician's experience as a derivative in searching for an optimal solution. This can be a new paradigm and main reason in the successes of various applications.

The goal of this book is to introduce major advances of the harmony search algorithm in recent years. The book contains 14 chapters with the following subjects: State-of-the-art in the harmony search algorithm structure; robotics (robot terrain and manipulator trajectory); visual tracking; web text data mining; power flow planning; fuzzy control system; hybridization (with Taguchi method or SQP method); groundwater management; irrigation; logistics; timetabling; and bioinformatics (RNA structure prediction).

This book collects the above-mentioned theory and applications, which are dispersed in various technical publications, so that readers can have a good grasp of current status of the harmony search algorithm and foster new breakthroughs in their fields using the algorithm.

Considerable activity in the acoustics of wood has occurred since the first edition of this book in 1995. An informal survey of a number of the published articles and papers presented at international conferences revealed that the interest of the wood science community is continually increasing. In this context, I felt c- pelled to revise the text in accordance with newer findings and this prompted the addition in the present book of 159 new references added to the existing 850 in the first edition. As a result of the favorable comments upon the first edition, from students and colleagues, I have included a part on mathematical theory related to wave pro- gation in orthotropic solids in the general text, in order to enable the interested reader to follow the essentially physical aspects of the subject. A new chapter related to "acousto-ultrasonics" is introduced; Chapters 4, 5, 6, 8, 9, 10, 11, and 12 have been considerably expanded and a significant redistribution of the subject matter from the earlier edition has been made.

The classic acoustics reference! This widely-used book offers a clear treatment of the fundamental principles underlying the generation, transmission, and reception of acoustic waves and their application to numerous fields. The authors analyze the various types of vibration of solid bodies and the propagation of sound waves through fluid media.

Ando establishes a theory of subjective preference of the sound field in a concert hall, based on preference theory with a model of human auditory- brain system. The model uses the autocorrelation function and the interaural crosscorrelation function for signals arriving at two ear entrances and considers the specialization of human cerebral hemispheres. The theory may be applied to describe primary sensations such as pitch or missing fundamental, loudness, timbre, and duration. The theory may also be applied to visual sensations as well as subjective preference of visual environments. Remarkable findings in activities in both auditory-brain and visual-brain systems in relation to subjective preference as a primitive response are described.

November, 2008 Anna Schwarz, Johannes Janicka In the last thirty years noise emission has developed into a topic of increasing importance to society and economy. In ?elds such as air, road and rail traf?c, the control of noise emissions and development of associated noise-reduction techno- gies is a central requirement for social acceptance and economical competitiveness. The noise emission of combustion systems is a major part of the task of noise - duction. The following aspects motivate research: * Modern combustion chambers in technical combustion systems with low pol- tion exhausts are 5 - 8 dB louder compared to their predecessors. In the ope- tional state the noise pressure levels achieved can even be 10-15 dB louder. * High capacity torches in the chemical industry are usually placed at ground level because of the reasons of noise emissions instead of being placed at a height suitable for safety and security. * For airplanes the combustion emissions become a more and more important topic. The combustion instability and noise issues are one major obstacle for the introduction of green technologies as lean fuel combustion and premixed burners in aero-engines. The direct and indirect contribution of combustion noise to the overall core noise is still under discussion. However, it is clear that the core noise besides the fan tone will become an important noise source in future aero-engine designs. To further reduce the jet noise, geared ultra high bypass ratio fans are driven by only a few highly loaded turbine stages.

The 26th International Symposium on Shock Waves in G ttingen, Germany was jointly organised by the German Aerospace Centre DLR and the French-German Research Institute of Saint Louis ISL. The year 2007 marked the 50th anniversary of the Symposium, which first took place in 1957 in Boston and has since become an internationally acclaimed series of meetings for the wider Shock Wave Community. The ISSW26 focused on the following areas: Shock Propagation and Reflection, Detonation and Combustion, Hypersonic Flow, Shock Boundary Layer Interaction, Numerical Methods, Medical, Biological and Industrial Applications, Richtmyer Meshkov Instability, Blast Waves, Chemically Reacting Flows, Diagnostics, Facilities, Flow Visualisation, Ignition, Impact and Compaction, Multiphase Flow, Nozzles Flows, Plasmas and Propulsion. The two Volumes contain the papers presented at the symposium and serve as a reference for the participants of the ISSW 26 and individuals interested in these fields.

This textbook gives a detailed explanation of waves and oscillations in classical physics. These classical phenomena are dealt with at a more advanced level than is customary for second-year courses. All aspects of classical wave physics are presented, including the mathematical and physical basis needed for extended understanding. Finally several chapters are devoted to important topics in current wave physics. Special attention is given to nonlinear waves, solitons, chaotic behavior and associated phenomena. The new edition contains improvements such as full development of Greens functions, a broadening of the treatment of wave mechanics and a closer integration with classical mechanics, plus more examples and problems.

The 29th International Symposium on Acoustical Imaging was held in Shonan Village, Kanagawa, Japan, April 15-18, 2007. This interdisciplinary Symposium has been taking place every two years since 1968 and forms a unique forum for advanced research, covering new technologies, developments, methods and theories in all areas of acoustics. In the course of the years the volumes in the Acoustical Imaging Series have developed and become well-known and appreciated reference works.

Offering both a broad perspective on the state-of-the-art in the field as well as an in-depth look at its leading edge research, this Volume 29 in the Series contains again an excellent collection of seventy papers presented in nine major categories: (1) Strain Imaging, (2) Biological and Medical Applications, (3) Acoustic Microscopy, (4) Non-Destructive Evaluation and Industrial Applications, (5) Components and Systems, (6) Geophysics and Underwater Imaging, (7) Physics and Mathematics, (8) Medical Image Analysis, (9) FDTD method and Other Numerical Simulations.

Humans have always been fascinated by marine life, from extremely small diatoms to the largest mammal that inhabits our planet, the blue whale. However, studying marine life in the ocean is an extremely difficult propo- tion because an ocean environment is not only vast but also opaque to most instruments and can be a hostile environment in which to perform expe- ments and research. The use of acoustics is one way to effectively study animal life in the ocean. Acoustic energy propagates in water more efficiently than almost any form of energy and can be utilized by animals for a variety of purposes and also by scientists interested in studying their behavior and natural history. However, underwater acoustics have traditionally been in the domain of physicists, engineers and mathematicians. Studying the natural history of animals is in the domain of biologists and physiologists. Und- standing behavior of animals has traditionally involved psychologists and zoologists. In short, marine bioacoustics is and will continue to be a diverse discipline involving investigators from a variety of backgrounds, with very different knowledge and skill sets. The inherent inter-disciplinary nature of marine bioacoustics presents a large challenge in writing a single text that would be meaningful to various investigators and students interested in this field. Yet we have embarked on this challenge to produce a volume that would be helpful to not only beginning investigators but to seasoned researchers.

Users of signal processing systems are never satis?ed with the system they currently use. They are constantly asking for higher quality, faster perf- mance, more comfort and lower prices. Researchers and developers should be appreciative for this attitude. It justi?es their constant e?ort for improved systems. Better knowledge about biological and physical interrelations c- ing along with more powerful technologies are their engines on the endless road to perfect systems. This book is an impressive image of this process. After "Acoustic Echo 1 and Noise Control" published in 2004 many new results lead to "Topics in 2 Acoustic Echo and Noise Control" edited in 2006 . Today - in 2008 - even morenew?ndingsandsystemscouldbecollectedinthisbook.Comparingthe contributions in both edited volumes progress in knowledge and technology becomesclearlyvisible: Blindmethodsandmultiinputsystemsreplace"h- ble" low complexity systems. The functionality of new systems is less and less limited by the processing power available under economic constraints. The editors have to thank all the authors for their contributions. They cooperated readily in our e?ort to unify the layout of the chapters, the ter- nology, and the symbols used. It was a pleasure to work with all of them. Furthermore, it is the editors concern to thank Christoph Baumann and the Springer Publishing Company for the encouragement and help in publi- ing this book.

When you listen to music at home, you would like to have an acoustic impression close to being in the concert hall. This is achieved by an advanced two-loudspeaker technique and electronic handling of the signals. The way to head-related sound reproduction and reception to get the original impression is explained in this comprehensive book on the outer influence of hearing and how to achieve perfect stereo effects. The book also introduces a theory of drift thresholds.